1. Field of the Invention
The present invention relates to tape cartridges for use with tape printing machines and more particularly to variable capacity reusable dual tape distribution cartridges.
2. Description of the Prior Art
The use of tape printing machines to produce adhesive lettering tape for labeling purposes such as those disclosed in U.S. Pat. Nos. 3,912,064 and 3,834,507 is increasing. Tape cartridges are a means by which to load tape into and dispense tape from the tape printing machines.
Dual tape dispensing cartridges are known in the prior art. Such cartridges are described in U.S. Pat. Nos. 2,107,603 and 4,226,547. A dual tape dispensing cartridge is also marketed by the Repeat-o-Type Manufacturing Corporation of Wayne, N.J. under the trademark "TYPE-Tape". The cartridges described in the patents and the Repeat-o-Type cartridge are capable of simultaneously dispensing two different types of tape. U.S. Pat. No. 4,226,547 and the Repeat-o-Type cartridge are specifically designed to work in conjunction with the aforementioned printing machines.
The use of single tape dispensing cartridges would have disadvantages when used with todays printing machines. One disadvantage would concern the amount of space required to house two cartridges within the machine. The increased amount of space would result in higher manufacturing and material costs for the printing machines. Furthermore, the increased cost of two cartridges would decrease the economic feasibility of use of such with present day tape printing machines. These problems have been partially avoided by systems wherein the two tapes utilized by the printing machines are simultaneously dispensed by a single tape cartridge.
In utilizing a dual dispensing tape cartridge it is necessary that the cartridge be simple to load and unload from the machine while maintaining the lowest parts, manufacturing and packaging costs possible.
One disadvantage of the conventional dual tape cartridge is that they are expensive to manufacture and package.
Another disadvantage of conventional dual tape distribution cartridges especially, when used with the aforementioned type printing machines, concerns the limited amount of tape able to be stored in each cartridge requiring time to be wasted in loading and unloading the tape cartridges when the tape has played out.
A further disadvantage of the conventional dual distribution tape cartridge design concerns the method by which tape is prevented from moving backward into the cartridge. Neither the Repeat-o-Type cartridge or the cartridge disclosed in U.S. Pat. No. 2,107,603 prevent tape back slippage while the cartridge disclosed in U.S. Pat. No. 4,226,547 utilizes a sharp edged spring clip as a tape back stop, which under some circumstances may damage the tape.